Pump



y Aug. 6, 1 929.

E. P. LARSH PUMP Filed oct. 19. '1925 3 Sheets-Sheet Aug. 6, 1929. E, P, ARSH 1,723,360

PUMP

Filed Oct. 19. 1925 5 Sheets-Sheet 2 E. P LARSH Aug. 6, 1929.-

PUMP

Filed Oct.l 19. 1925 C5 Sheets-Sheet 3 Patented Aug. 6, 1929.

UNITED STATES PATENT OFFICE.

llVllRE'lfl l?. LARSH, OF DAYTON, OHIO, ASSIGNOR T0 THE MASTER ELECTRIC COM- PANY, OF'DAYTON, OHIO,

A CORPORATION OF OHIO.

PUMP. i

Application filed October 1'9, 1925. Serial No. 63,392.

My invention relates to pumps and fluid pressure motors of the expanding chamber type. The invention is particularly applicable to hydraulic pmnps, although not limited to such application, but may be utilized for delivering under pressure, various h quids or fluids, and when combined with suitable valve gear, the primary features herein shown and described may be utilized as a fluid` pressure motor. i

The structure forming the subject matter hereof, utilizes in con'ibination, the more advantageous characteristics of a diaphragm pump and those of a reciprocating piston pump or motor. 4 In the present invention, there is contemplated ya pressure chamber having spaced flatparallel side walls, the chamber being divided into compartments alternately expansiblc and contractible by an intermediate flexible partition wall. The partition wall is fixedly connected at its ends to the end walls of the chamber, while the intermediate portion is capable of to and fro warping movement, in which the lateral margins of the flexible wall are free for to and fro sliding or wiping enojagement upon the spaced parallel flat side walls of the .chamber. rl`he flexible partition wall 1s given a vibratory movement to alternately extend and contract the respective compartments by means of crank shaft connected withthe flexible partition wall at a medial point by a connecting rod or pitman. Inlet and discharge valves are located on opposite sides of the flexible partition wall affording inlet and outlet passages to the respective compartments. The construction necessitates minimum clearance requirement, while alici-ding a maximum displacement in relation to the total full piston movement. f

The structure as a whole forms a small compact unit, capable of being mounteddirectly upon the head of an electric motor1 or being mounted as a separate unit for high speed operation, and possesses high eicienf cy, and a large output capacity,"in comparison with. the power requirements. y

The object of the invention is to simplify the structurey as well as the'means and mode of operation of fluid pressure devices, whereby they will not only be cheapened in construction, but will be more efficient in use, positive in operation, uniform in action, and unlikely to get out of repair. y

A further object of the invention is to provide' a pump or like construction, having a minimum number of parts, and of simple, compact construct-ion, necessitating but u, smally amountk of machine operations, and therefore, economical in manufacture and maintenance. f

A further object. is to provide a pump or like device, of high eliiciency, and maximum output with minimum power reouirement.

, A further object of the invention is to proi vide a flexible piston construction which will embody the advantageous characteristics of a diaphragm while eliminating the objectionable features thereof.

A further object of the invention is to provide a large capacity continuous flow pump having a short stroke.

.A further object of the invention is to provide an improved form of valve and valve seat mounting.

lVith the above primary and other incidental objects in view as will more fully appear in the specification, the invention consists of the features of construction, the parts y and combinations thereof, and the mode of operation or their equivalents as hereinafter` described and set forth in the claims.

In the accompanying drawings, wherein is shown the preferred, butobviously not necessarily the only form of embodiment of the invention, Fig. l is a vertical sectional view of the assembled pump structure form ing the subject matter hereof. Fig. 2 is a transverse sectional view thereof, on line 2 2 of F l, viewed toward the left, to illustrate rthe compression chamber and flexible piston wall. Fig.r 3 a similar view on the same plane, but viewed toward the right, showing thc location of the inlet and discharge port, and by dotted lines, the relative position of the compression chamber, and flexible piston. F ig. i is an exterior view showing the discharge hcadin elevation. Fig. 5 is a detail perspective view of the flexible piston, removed .from the chamber. Fig. G illustrates a modification wherein the flexible piston comprises a succession of hinged jointed sections. Fig. 7 is a transverse sectional View of the fluid supply and discharge` chambers, and the relief valve therebetween. Fig. 8 is a vertical sectional view on line 8-8 of Fig. 7.

Like parts are indicated by similar characters of reference throughout the several views.

llO

. other ileXible composition materials may be employed, or in lieu thereof, a pointed metallic piston wall may be utilized. rrlhe piston For simplicity ano economy ot manufacture, the pump casing` or housing has been shown as comprising a series of plates or parallel sections arrange l side by side. rlhe tiret ot these sections comprises the head 1, which has been shown provided with a supporting bracket or toot 2, and with a laterally projecting boss or bearing,- sleeve 3, to receive the orive shaft et. lThis drive shaft d, may comprise the armature shaft of' an electric motor, of which t-he primary head 1 forms a part o the motor casing. Otherwise the. shaft L1 may carry a. driven pulley or gear actuated from any suit-able source ot power. By constructing the head 1 as separate member. the face of the head may be conveniently and economically iinished by grinding' or otherwise to afford a substantially unitorm liat surface. The pump chamber 5 comprises a recess or opening, through a main disc or plate G, which is positioned against the. lia't Ilace of the primary head 1, which .terms one of the lateral or side walls et the pump chainber. The opposite side of the pump chamber is formed by the lat side or a plate 7, parallel with and bearing against the side of the main plate 6, to enclose the chamber 5. for which the flat engagement faces of the head and plate 7 form parallel spaced side wal The intermediate plate 7 is provided with a series ot circular openings registering with inlet and outlet valves 9 and 10, connnunicating with supply and discharge chambers ot a head 13, secured to the outer side of the plate T and enclosing therebetween the valve seats of the inlet and out-let valve dises le. rlhe pump chamber 5 is of trilobular shape, the upper lobe ot the chamber being oiFY substantially circular form, to accommodate a crank head 15, upon the drive shaft a. To insure uniform smooth operation, the crank 15 of the balanced type. The chamber 5 is sei, arated into two non-communieating` compartments, by means of a. transverse flexible wall or partition 1 6. This flexible Wall or partition 1G performs the function of a piston and Vpossesses' certain characteristics of both a diaphragm and a reciprocatory piston head. The 'flexible piston wall or partition is prererably :formed `from a leather strap, although strap or partition, whether ot leather or other flexible composition material, is either formed of two superposed laminations, or it a single piece of suthcient thickness is employed, such strip of material is scored along),l its longitudinal lateral margins to lio-rm parallel tongues or beads, which are turned in opposite directions to `form two channel surfaces, oppositely disposed. rlhe ends of' tl e llexible piston wall nor strap are secured in the end walls of the pump chamber 5. These end walls are provided with small recesses or socket openings 17, to receive the terminal ends or" the tlexible piston strap, which are securedv therein by any suitable attachment means, as tor example, wooden wedges 1S, driven tightly into the recesses er openings 17, to clamp the ends of the piston wall or strap therein. This piston wall or strap is of such width to exactly lit the interior of the chamber, intermediate its dat parallel side walls, against which the out-turned beads or {ianges formed by the marginal scoring` of the strap have tree wiping or sliding` engagement. llhile the intermediate flexible wall or piston strap is xedly secured to the walls of the pump chamber at its opposite ends, the intermediate portions of uch flexible wall or piston strap is free tor warping or vibratory movement within the chamber, during which the margins ot the straps or ileilible wall move to and tro upon the flat parallel side walls somewhat in the manner ot a. reciprocatory piston. The upturned marginal ede/jes o1 the strap forming oppositely disposed channel surfaces perform the function of a. cup leather to seal the contact between the flexible piston wall and the paralicl side walls of the chamber to prevent leakrom one compartment to the other ot the chamber, past such wall or piston strap. rhis flexible i 1all or piston strap is medially connected to the crank 15, by a pitman or connectingh rod 19, mounted at one end upon the crank 5, and having its other end ecured to the piston strap. Preferably, caring plates 2O are provided upon opposite sides of the piston strap or flexible wall, a1 the point of attachmentof the connecting;- rod 19. rllhese bearing plates extend on opposite sides of the connecting rods, throughout a range of approximately one third the length oi the fle-sible piston strapor wall. These bearing plates are slightly curved away from the strap at their extremities and serve to distribute the bending strain. As the opcitdinioy crank shaft is r ated, the piston strap flexible wall 16 is given a vibrator); movement to and tro with a peculiar warping or undulating eiiiect, which in prac-tice has been found very effective in expelling water or other liquid from i'irst, one compartment, and then the other compartment or" the pump chaniber. Merely, as an example but with no intention of establishing,` proportions and relative sizes ot parts, it has been Jound in practice that a pump constructed as herein shown and described, wherein the crank shaft ha, three eights inch throw, acting upon the piston wall or strap, having an eiilective length ot three inches in a pump chamber, approximately one halt nch in width, develops a discharge output ot two hundred gallons per hour under a power requirement or one-eighth horsepower.

The inlet compartment 11 ol the head 13, communicates with the respective compartlll) yany suitable and convenient construction, it

has been found by experiment that circular discs of resilient material or of flexible character, such as rubber or leather, held upon their seats by a centrally located stud or screw, are most satisfactory. The valve seats 14 comprise perforated discs of metal,

preferably of concavo-convex form. These valved seat discs are clamped between the intermediate plate 7, and the pump head 13, or may be fixedly secured in the circular registering openings of either of these members by pressing the plate into the opening under sufficient pressure to reduce the convexity of the valve seatplate and thereby expand them into firm engagement within the opening'. The flexible valve discs 9, are located upon the concave side of such valve seat discs and extend into overlapping relation with the perforations 19 of such discs. By locatingl `the flexible valve discs 9, upon theconcave side of the discs 14, the peripheries of the valve members adhere closely to the corresponding seats.

As a safetyfprecaution, a relief valve 25 is provided rbetween the discharge chamber 12Iand the intake chamber 11 of the head 13. These chambers or compartments have overlapping recesses 21 and 22, in the partition between which is located the valve seat 23, upon which the valve 25 normally rests, under the influence of the spring 2li. However, in the event of excessive back pressure in the discharge line, this valve will open to automatically relieve such back pressure, by perinitting a return flow to thesuction side of `the pump.

From the above description, it will be apparent that there is thus provided a device of the character described possessingr the particular features of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts, lwithout departing from the principle involved `or sacrificing any of its advantages.

While in order to comply with the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the` invention is not limited to the specific details shown, but that the means and construction herein disclosed comprises the preferred form of several modes of putting the invention into effeet and the invention is, therefore, claimed in any of its forms or modifications within the `legitimate and valid scope of the appended claims. y

Having thus described my invention, I claim:

1. In a construction of the character described, a chamber having spaced parallel side walls, inlet and outlet ports leading to and from said chamber, a continuous partition of flexible material in said chamber, separating the chamber into alternately expansible an-d contractible compartments having its opposite ends engaged in fixed relation with the walls of the chamber and the me.- dial portion having sliding contact upon the spaced parallel side walls, and means for flexing the partition to and fro to vary the capacity of the compartments.

2. In a construction of the character described, a chamber having spaced parallel side walls, inlet and outlet ports leading to and from the chamber, an integral continuous flexible wall for said chamber interposed between the spaced parallel side walls, the opposite ends of the flexible wall being fixed,

the intermediate portion of the flexible wall being capable of a to and fro bending movenient, in which the opposite lateral margins of the flexible wall have to and frowiping engagement uponthe spaced parallel side walls of the chamber, and means to vibrate the flexible wall.

3. In a construction of the character described, a chamber having spaced parallel side walls, inlet and outlet ports leading to and from the chamber, a unitary flexible diaphragm in said chamber comprising a single piece of material having two opposite fixed margins and two opposite free margins, the latter having sliding contact upon the spaced parallel side walls of the chamber, a crank and a connecting rod connecting the crank with the medial portion of said diaphragm.

el. In a construction of the character described, a easing having internally two opposite fiat walls, a continuous partition of flexible material interposed between the flat walls having its ends fixed and its medial portion capable of to and fro warping movement in which the lateral margins of the flexible partition have free sliding Contact upon the internally flat walls of the casing, a revoluble crank shaft, a connecting rod connecting the flexible partition medially with the crank shaft and valved inlet and outlet ports communicating with the casing on opposite sides of the flexible partition.

5. In a fluid pressure apparatus of the character described, a pressure chamber, a flexible piston member therein of elongated strip form, the ends of said piston being fixedly secured, and the longitudinal side margins being free, oppositely extending' flexible lips on the side margins of said piston strip, the medial portion of said flexible piston being capable of to and fro warping movement and ing interior@Y opposite flat Walls, a continuous Llezrible Dartition strip ot greater length l than tlie distance across tlie eliainber ing across die olianiber in perpendicular relation, to tilie flat side Walls, and Capable ol `o and l'ro warning inoveinent therebetween, tlie extend l ends oi tlie flexible strip being 'ixedly secured Wliile tlie loiigitudina` inargiis are 'free for to and tro wipingK en: t

Y gement upon Vdie liat side Walls duri the warping inoi'oinent oit the vllexible pa' tion and sealing ineans i'or elle/citing a leali tight contact between the -Wiping' n argiiis of tlie partition and tbe flat Walls or tlie Cliaiiiber.

i. in iiuid pressure apparatus ot tl'ie character describen, pressure cliainber liarinteriorly opposite dat Wil s, and a 'liese strap piston capable ot to an( l'ro Warpirioveinent, extending interni-er iz te tlie lrel alls and in perpendicul itli its opposite ends gitudinal niargins free a Contact ipon tlie nat- Wa`= t i said strap piston being` of l l iannel sliape and haring flexible iiiarg nal tang-es pressed into Contact Witii tlie l t side Walls by iluid pressure Within die cliainber.

S. In a. tluid pressure apparatus ot tlie character described, a p 'fessure cliainber liaving interiorly opposite flat. Valls, and a lle:- ible strap piston capable oi to and tro Warping inoveinent, extending intermediate tlie flat Walls and in perpendicular relation Jdiereto, Willi its opposite e'ids attaclied a id its lon- `t it inail margins i'iree for to and Jiro wiping,` Contact upon the ilat Walls ol tlie chamber, said strap piston being longitudinally scored upon its tree edges, and oppositely disposed marginal Jhinges forined t-liereon by suoil marginal scoring, uliicl flanges are 't tlie llat si iro,

into sealing Contact Wirli by luid pressure Within tlie eliaiiib r.

9. ln a iluid pressure apparafu;J

character describen, a pressure cliaiiiier, naving iiiteriorlj,Y opp site Walls, i

ible strap piston c :i able or' to an l tr in inoveinent, enteiiding intermedia fiat Walls and in peiiiiendicular relation *o with its opposir L git-udinal margins ends attC clied an@ its ree for to and iro Wil Contact uson tlie flat Walls of the cliainber, a Cranlr shalt, a connecting rod attaches to said lexible pistoi at ainedial point, L nd bearing plates located on opposite sides or' tlie iiexible piston and extending` in opposite directions frein tlie pointot attachment of said connecting rod tliereto.

l0. ln a fluid pressure apparatus or the liaracter described iressure cliainbenliai's apparatus ot tlie ible piston capable of to and iro Warping nioif'eiiient, extending intermediate tlie 1ls and in perpendicular rela tion there- "li its opposite ends attached and its o" Audinal margins free Jroi' to and tro Wiping een act upon tliellat Walls o bei', tlie intermediate portion o t tlie cliainlie partition beii g rendered resistant to flexing ovenieiit While ellecting to and niovei ien in unison die ieiiing inoveinent of tlie partition r b Willi t opposite sides or suoli intermediate porn pressure chamber, Lravp e :dat Walls, and a le'- on capable ot to and tro Warptl etending` intermediate the n in perpendicular relation e sides ol-tlieclainp plates.

iony whereof, l liae liei unto set 'nis 28th day or September A. D.

ini: liant ieee.

EVERETT R LABSH. 

